Cavitation is frequently encountered in liquid pipelines when regulators are employed to reduce pressures substantially from a relatively high initial level. Cavitation, in turn, may produce excessive noises and unstable operation, and may result in damage to the regulators and associated piping. Previously, others have solved the problem of cavitation by reducing the liquid pressure in two or more stages. However, such multi-stage systems often result in unstable or cycling operations when pilot operated regulators interact with one another.